A new study by U.S. researchers questions the safety of giving birth at home, suggesting that more babies die during home births than during hospital deliveries. But Canadian researchers, whose data were extracted and used in the study, say that conclusion is deeply flawed.

The meta-analysis of 15 studies, led by Joseph Wax of the Maine Medical Center's department of obstetrics and gynecology, found that giving birth at home tripled the risk of neonatal death.

Patricia Janssen, an associate professor at the University of British Columbia's school of population and public health, says that conclusion is "sensationalist" and based on data that are in some cases decades old, on very small samples and in some cases incomplete.

In many cases, she says, women included in the studies may not have planned to give birth at home. They may not have been attended by a properly trained midwife. And much of the data used were retrospectively, gathered using birth records, which may not include enough information.

Dr. Janssen's most recent research, published last September, found no difference in outcomes between planned hospital births and planned home births. Similar results were found in an Ontario study.

The question of whether there's a higher risk of a baby dying during a planned home birth with a regulated midwife has been answered in Canada, she says.

"The question has not been answered in the United States."

In the new meta-analysis, researchers looked at a total of 342,056 home births and 207,551 hospital births in Canada, the United States, the Netherlands, Britain, Australia, Switzerland and Sweden.

While home births were associated with fewer complications for mothers, including lacerations, bleeding and infections, their babies didn't fare as well. Although there were fewer premature births, babies with low birth weights and babies with respiratory problems than those born in hospital, the mortality rate appeared higher.

Canadian researchers say only the Canadian and Dutch data were as rigorous as they should be.

Michael Klein, emeritus professor of family practice and pediatrics at the University of British Columbia, says the analysis and its conclusion has to do with the climate in the United States around midwifery. It is less accepted by the medical profession there than it is in Canada, he said.

"We're dealing with a politically motivated study," said Dr. Klein, who was a co-author with Dr. Janssen on the B.C. study.

Dr. Wax could not be reached for comment. His study was published Thursday in the American Journal of Obstetrics and Gynecology.